In recent years, silver halide color photographic light-sensitive materials have been subjected to high temperature, accelerated processing for conducting rapid processing. Also, preparation of large size silver halide grains, enhancement of activity of the color couplers used, and addition of development accelerators or development accelerator-releasing compounds to light-sensitive materials have been employed for enhancing the sensitivity of the light-sensitive materials.
However, these techniques cause serious problems such as an increased fog of the silver halide color light-sensitive materials or more increased fog after preservation of them as unexposed materials.
In addition, hardeners having an active vinyl group, which have come into wide use for accelerating the progress of hardening after silver halide emulsions are coated on a support, cause an increased fog in comparison with triazine type hardeners, and the fog is more increased after preservation of the unexposed light-sensitive materials.
As one technique to solve the problem of fogging, it has been known to add various antifoggants for preventing fogging of silver halide color photographic light-sensitive materials and increased fogging after preservation of the light-sensitive materials as unexposed light-sensitive materials.
That is, many compounds such as azoles [e.g., benzothiazolium salts, nitroindazoles, triazoles, benzotriazoles, benzimidazoles (particularly nitro- or halogen-substituted benzimidazoles)]; heterocyclic mercapto compounds [e.g., mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, mercaptotetrazoles (particularly 1-phenyl-5-mercaptotetrazole), mercaptopyrimidines, etc.]; thioketo compounds (e.g., oxazolinethione); azaindenes [e.g., tetraazaindenes (particularly 4-hydroxy-substituted (1,3,3a,7)tetraazaindenes, etc.)]; benzenethiosulfonic acids; benzenesulfinic acids; etc., known as antifoggants or stabilizers can be added.
As to more specific examples thereof and manners of their use, reference may be made to, for example, U.S. Pat. Nos. 3,954,474, 3,982,947, 4,021,248, etc., or Japanese Patent Publication No. 28660/77.
However, application of the above-described antifoggants to color photographic light-sensitive materials cause various side effects, which impose restrictions on the amounts of them to be added. Thus, sufficient antifogging effects cannot be attained.
U.S. Pat. No. 3,376,310, for example, discloses a technique of using phenylmercaptotetrazoles with a diffusion-preventing ballast group to provide the antifogging effect of the compounds selectively on a specific layer. The antifoggants inhibit development so much that direct addition of the antifoggants to light-sensitive materials is not preferable because it causes reduction of sensitivity and deterioration of gradation. Furthermore, Japanese Patent Publication No. 9939/83 (corresponding to U.S. Pat. No. 4,021,248), for example, discloses that heterocyclic mercapto groups having at least one group selected from --SO.sub.3 H, --COOH, --OH or --NH.sub.2 can depress fog without serious deterioration of sensitivity and gradation. Of the compounds disclosed therein, phenylmercaptotetrazoles having --COOH or --SO.sub.3 H are found to cause an extremely slight reduction of sensitivity and deterioration of gradation and depress fogging of light-sensitive materials and increased fogging after preservation of unexposed light-sensitive materials. However, the compounds have problems in that they dissolve into a developer and thus change the properties of the developer. Further, when light-sensitive materials containing the compounds are developed with a developer having its activity reduced by a development-inhibiting substance dissolved therein, the light-sensitive materials suffer more reduction of sensitivity or more deterioration of gradation as compared with the other light-sensitive materials.